氮化硅铁加入量对镁质浇注料力学性能的影响

Effects of Fe-Si_3N_4 Addition on the Mechanical Properties of MgO-based Castables

以镁砂为主要原料,以硅微粉作为结合剂,研究了不同氮化硅铁加入量对镁质浇注料常温物理性能和高温力学性能的影响,借助X射线衍射仪、扫描电镜等对浇注料的物相和显微结构等进行了分析。结果表明:随着氮化硅铁加入量的增加,浇注料烘干强度下降,中温强度先变大后变小,在氮化硅铁加入量为3%时达到极值点,高温强度先增大后下降;热态抗折强度在氮化硅铁加入量为3%时达到最大。氮化硅铁在加热过程能部分氧化成二氧化硅,进而形成纤维状的镁橄榄石,增大强度;铁相物质能和方镁石固溶,促进烧结。

The effects of Fe-Si3N4 addition on the room temperature physical properties and hot mechanical properties of MgO-based castables using magenisite as main raw and micropowder as binder were investigated.The phase and microstructure were analysed by XRD,SEM.The results show that as the increase of Fe-Si3N4 addition the drying strength decreases.The immediate temperature strength increases first and then decreases and the maximum value is obtained when 3% Fe-Si3N4 is added.High temperature strength increases first and then drops.The hot modulus of rupture maximizes when 3% Fe-Si3N4 is added.Fe-Si3N4 partially oxidizes to produce SiO2 and further tranforms to fibrous M2S contributing to strength.The phase containing iron can produce solid solution with magnesia contributing to sintering.